1. Field of the Invention
The present invention pertains to a method for reinforcing a wavefield in a dual wavefield environment and more particularly to reinforcing a wavefield in a dual wavefield environment with an offset.
2. Related Prior Art
Pressure and velocity detectors are used to separate upward traveling waves (U), from downward traveling waves (D), in a seismic experiment. For the case of pressure and particle velocity detectors located on the water bottom, a method is described in U.S. Pat. No. 4,935,903, Sanders et al., where the downward traveling waves can be used to reinforce the upward travelling waves. In this method, D is time shifted by the vertical two-way travel time of the water column to align (in time), with U. The two wavefields are added together to produce pre-stack reinforced data.
The method described in U.S. Pat. No. 4,935,903, titled "Reinforcement of Surface Seismic Wavefields" relates to a marine seismic reflection prospecting system that attenuates coherent noise through reinforcement of primary reflection data by the addition of corrected ghost reflection data. The system described includes a seismic energy source, a detector, a wavefield separator, a time shift element, and an element for generating an output signal representative of an additive linear combination of time aligned primary and ghost signal components. The system's output is suitable for further pre-stack processing, e.g., NMO correction.